That settled, I have been investigating the question of how well Windows 7 (64) runs Second Life. It installed and runs for me (Ultimate edition) with no problems. I have now heard of at least 6 other instances of people installing and running Windows 7 (64) of various editions.

-I see that my system has two program directories, one called Program Files (x86) and the other called just Program Files. My Second Life run files are in the (x86) directory, as are most of the other legacy programs I have installed. My guess is that this directory is for programs that need to run in a 32 bit mode and that Win 7 usually detects that condition and installs in the correct directory. -I have heard of problems with other software (Icecast) under Win 7/64. Here are general instructions for handling such problems via the compatibility wizard included in Win 7:Windows 7 compatibility: Solving Hardware, software issues: -

"Compatibility ModeIf you do run into an application that won't work properly in Windows 7, first try to run it within a special emulation mode called compatibility mode. This enables you to trick the application into thinking it is running on an older version of Windows. There are two ways to trigger this functionality: automatically via a wizard, or manually via the Explorer shell. There's also a third related function, the Program Compatibility Assistant, which appears automatically when Windows 7 detects you're having a problem installing or using an application."